  Proper radium watch hands, Bestfit 6R4 kit.
After being burned by the "radium" paint described above, I was a bit nervous about these watch hands, also from eBay. Fortunately, all but 3 of the glass vials full of watch hands turned out to be highly radioactive. None of them glow (the zinc sulfide phosphors break down after only a few years, so old radium hands don't glow even though the radium itself has a half-life of 1600 years).
Interestingly, while they all glow somewhat after exposure to bright light, the non-radioactive ones glow more than the others. Two possibilities come to mind: Perhaps they were never meant to be radioactive, and are a made with a newer, simple glow-in-the-dark paint. Or perhaps they were defectively manufactured, and the phosphor has simply survived better because it isn't being exposed to constant radioactivity. Given that they appear identical to the radioactive ones and are in exactly the same kind of container, I would tend to think the latter. The hands all constitute a single kit of replacement hands, so one would expect them all to be from the same era. On the other hand, perhaps the non-radioactive ones are the most popular sizes, and had to be re-stocked with newer hands at a later date, to keep the kit complete.
This excellent book has a photograph (on page 83) of a very similar full set (Bestfit 6R5), in its original box. I have the label that came with the set, but not the box.
Source: eBay seller dashto
Contributor: Theodore Gray
Acquired: 4 November, 2002
Price: $37
Size: 0.5"
Purity: <1%
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